Ah. I see how you are using it now. Though I can't say I completely agree with it. Why not return `s` by reference. Then, you could use:
```D
SetFileAttributesW(name.toUTFWz(sz)[].ptr, attributes);
//or, with .ptr as a member property:
SetFileAttributesW(name.toUTFWz(sz).ptr, attributes);
```